A product key
is a 25-digit number that's used to activate Windows 8/8.1. Activation helps verify that Windows hasn't been used on more PCs than the Microsoft Software License Terms allow.
Your product key should be in the box that the Windows DVD came in, or in an email that shows that you bought Windows.
It looks like this: PRODUCT KEY: XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
While performing a clean or upgrade install of a retail copy of Windows 8/8.1
or Windows 8/8.1 Professional
, Microsoft requires that you enter the product key for it during installation and will be automatically activated when online.
All OEM PCs
that come with Windows 8/8.1 or Windows RT/RT 8.1 preinstalled
will activate automatically when they are connected online to the internet. The product key is embedded in the UEFI/BIOS firmware of OEM PCs with Windows 8 preinstalled, and is entered automatically for activation.
When installing Windows 8/8.1 Enterprise
, it doesn't ask for a product key number and isn't activated automatically since Microsoft allows you to use a free 90-day evaluation
of Windows 8 Enterprise
or Windows 8.1 Enterprise Preview
before needing to purchase a license (product key). Windows 8 Enterprise can be activated online by changing the product key number
to the one you purchased with the Windows 8 Enterprise.
However, sometimes after you change hardware (ex: motherboard), install the same Windows 8 on a new replacement computer, or some other activation error, Windows 8 may become no longer activated. If you are unable to activate Windows 8 online as usual, then you may need to activate Windows 8 by phone instead.
This tutorial will show you how to activate Windows 8 and 8.1 by phone
when Windows 8 or 8.1 is already installed and you are unable to activate online with the product key.
You must be signed in as an administrator
to be able to activate Windows 8 by phone.